Radiation-emitting components, such as light-emitting diodes (LEDs), for example, often contain luminescent materials in order to convert the radiation emitted by a radiation source into a radiation having an altered, usually longer, wavelength. In this case, the efficiency of the luminescent material is dependent inter alia on its position of the absorption maximum in relation to the wavelength range of the primary electromagnetic radiation and/or on the position of its emission maximum. In particular, in the case of radiation-emitting components which emit warm-white light, high-efficiency luminescent materials are required which have an emission of electromagnetic radiation in the red range, for example in the range of greater than or equal to 600 nm.